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In lake trout (Salvelinus namaycush) lakes of northeastern Ontario, Canada, aerial surveys of fishing activity on individual lakes (N = 589) and quantitative gillnet surveys (N = 65) were used to assess the effects of road access on angling effort and the presence of introduced smallmouth bass (Micropterus dolomieu). Angling effort, particularly during the open-water season, was highest and often exceeded estimated sustainable levels on lakes with good road access. Approximately 25% of the remote lakes also received excessive pressure during the winter season. Angler numerical responses to lake trout abundance were detected in remote lakes, but not in road-accessible lakes. Smallmouth bass were more prevalent in lakes with road access and human settlement (either cottages or lodges), supporting the theory that they were introduced into these lakes. Lake trout populations were depleted throughout much of the study range. Even without road access or smallmouth bass, lake trout abundance was still 47% lower than in unexploited reference lakes. When bass and (or) road access were present, lake trout abundance decreased by 77%. Remote lake trout populations in this area are clearly vulnerable to the negative impacts of improved access, a vector for both overexploitation and species introductions. Des inventaires aeriens de l'activite de peche sur des lacs individus (N = 589) et des inventaires quantitatifs an filet maillant (N = 65) nous ont servi a evaluer les effets de l'acces routier sur l'effort de peche sportive et sur la presence d'achigans a petite bouche (Micropterus dolomieu) introduits dans des lacs a touladis (Salvelinus namaycush) du nord-est de l'Ontario, Canada. L'effort de peche, particulierement durant la periode d'eau libre, est le plus eleve dans les lacs facilement accessibles par la route et il depasse souvent le niveau admissible estime. Environ 25 % des lacs eloignes subissent aussi une pression excessive durant la saison d'hiver. On remarque une relation entre le nombre de pecheurs et l'abondance des touladis dans les lacs eloignes, mais pas dans les lacs accessibles par la route. Les achigans a petite bouche sont plus presents dans les lacs a acces routier et a presence humaine (chalets on auberges), ce qui laisse croire qu'ils ont ete introduits dans ces lacs. Les populations de touladis sont reduites dans presque toute la region d'etude. Meme en l'absence d'acces routier et d'achigans a petite bouche, l'abondance des touladis est tout de meme de 47 % inferieure a celle des lacs temoins non exploites. Quand il y un acces routier et (on) presence d'achigans, l'abundance des touladis est reduite de 77 %. Les populations eloignees de touladis sont visiblement vulnerables aux impacts negatifs de l'amelioration de l'acces routier, un vecteur representatif a la fois de la surexploitation et de l'introduction d'especes. [Traduit par la Redaction], Introduction Many of Canada's recreational fisheries have shown the effects of overexploitation (Post et al. 2002) or the impacts of invasive or introduced species (Vander Zanden et al. 2004b). However, [...]

Introduces the May 2003 special issue of 'AMBIO' which deals with the recovery of acid damaged lakes and rivers in Canada.